Trilium features customizable to-do list task states. To customize them, go to "Options""Text Notes""Related Settings""Custom checkbox states for to-do lists". Alternatively, right-click a checkbox in an editable text note and click the pencil icon.

Creating a new task state

Click the plus icon next to Task States in the left-side pane, then define the task details as described in the next section.

Editing a task state

Selecting any state other than "None" and "Done" (which cannot be modified) from the side pane reveals the following editable fields:

Reordering task states

To change the order in which task states appear in the UI and when cycling through them with the keyboard, simply reorder the states in the side pane (or tree panel, if it's the case).

Deleting task states

Any task state other than "None" and "Done" can be deleted.

Once deleted, to-do items using that state will no longer display the custom checkbox. They fall back to either a "None" or "Done" state, depending on the state's "Counts as completed" setting. The identifier and title remain stored in the note until you set the checkbox to a new state.

Transferring notes with custom task states between Trilium database instances

Exporting notes to another Trilium database instance preserves the task states of to-do items, but does not include the custom task definitions. As a result, the destination instance won't know how to render the checkbox unless you recreate the task state there with the same identifier and Markdown symbol.